A/C Problem

Hi guys...need some A/C help. I have had the A/C belt break on my 99 Z71 5.3 about 4 times so far. I have changed the tensioner and checked everything that I know. It has varied between lasting 2 weeks to lasting almost 2 months this last time. It makes no noise...cools VERY good...but breaks the belt. I climbed under the truck when I replaced it the last time and watched the belts and compressor thinking maybe the compressor was locking up from time to time...but ...I did not see any of this. The odd thing is.....there are scar marks on the outside of the belt...which is why I thought tensioner. Is there something I am missing? If the compressor were locking would the scar marks not be on the inside of the belt? It's too hot to not have it working...I appreciate any help you can be.

Check all of your pulleys sounds like perhaps one of your pulleys has some how worked it's way back or something? If it's the front of the belt perhaps it's not on all of the teeth properly? Also, maybe check each of your pulleys for dirt, teeth mashed, or anything else that maybe causing your pulley to hop?

The only other thing I could think of is that the A/C is compressor is getting worn out and when it switches on it switches on so harshly that it causes the belt to hop however, I don't think this is it as your Belt Tensioner should pickup that kind of thing...

Happy hunting...

Check all of your pulleys. Especially the ider pulley for scarring on the smooth surface. Since you have marks on the outside of the belt, check smooth pulleys that contact the outside of the belt. Like the tensioner, idler, and water pump pulleys. You could have a bearing intermittantly seizing up.

Check all of your pulleys. Especially the ider pulley for scarring on the smooth surface. Since you have marks on the outside of the belt, check smooth pulleys that contact the outside of the belt. Like the tensioner, idler, and water pump pulleys. You could have a bearing intermittantly seizing up.

It's a separate belt...there is only the one tensioner touching the outside of the belt.

Check all of your pulleys sounds like perhaps one of your pulleys has some how worked it's way back or something? If it's the front of the belt perhaps it's not on all of the teeth properly? Also, maybe check each of your pulleys for dirt, teeth mashed, or anything else that maybe causing your pulley to hop?

The only other thing I could think of is that the A/C is compressor is getting worn out and when it switches on it switches on so harshly that it causes the belt to hop however, I don't think this is it as your Belt Tensioner should pickup that kind of thing...

Happy hunting...

Everything looks good under there...the compressor is the only other thing I can think of. Like I said though....it just baffles me why the belt is scarred on the outside and not the inside if thats the case.